1. Field of the Invention
The invention relates to a battery electrode and a battery electrode manufacturing method in which an electrode layer having a multilayered structure can be easily formed.
2. Description of the Related Art
An electrode used in a chemical battery such as a metal-air battery, a lithium battery, and a fuel cell normally has a collector and an electrode layer formed on that collector. In recent years, attempts have been made to form the electrode layer with a multilayered structure in order to improve the performance of the battery electrode.
For example, Japanese Patent Application Publication No. 2006-286414 (JP-A-2006-286414) describes a positive electrode that is used in a nonaqueous electrolyte air battery and has two layers of different compositions. More specifically, JP-A-2006-286414 describes a positive electrode that has a layer which is able to reduce oxygen formed on the air hole side, and a layer which is able to store lithium ions formed on the negative electrode side. Also, in JP-A-2006-286414, various examples of methods for forming this kind of positive electrode are described, such as a forming two film-like layers and superposing these on the collector, or sequentially applying a composition that includes the components that form these layers.
Meanwhile, Japanese Patent Application Publication No. 7-320744 (JP-A-7-320744) describes an electrode that is used in a metal-air battery or a fuel cell and has an active layer that includes a catalyst and a water-repellent blocking layer. Also, JP-A-7-320744 describes a method for forming this kind of electrode that includes sequential deposition by filtering means using a dispersion fluid that includes the components that form the layers.
Both of the methods described in JP-A-2006-286414 and JP-A-7-320744 combine operations for forming single layers. As a result, there are a many manufacturing processes and the operation is complex.